[How do I?] Any tips for using the Drill Doctor x750?

HMF

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Well, I ordered a Drill Doctor X750 from Enco with the 15% off and web sale last Friday.

Now I need some tips on using it to produce good, sharp drills.

Can those of you who own one, please, give me some tips for good operation?

Thanks!



:tiphat:Nelson
 
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billinecin

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For me, same as Edk says. I wait until I have several to resharpen. Seems like even after watching the video and reading the manual, I still need to do a couple before I get the feel of things. Then I have to go back and redo those first couple.

Bill
 

bedwards

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The instructions are pretty good that comes with it. Just be smooth and even on each side when you grind and you should have no problems. I sharpened bits I have saved for years. It is pretty fast once you get the hang of it.



be
 

arvidj

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I'll add another vote for "Watch the video" and "not been able to get the split point to work".

At least for me the "secret" is in setting up the bit in the holder properly. The key for me was letting the spring metal fingers rotate the bit to get the proper axial orientation of the bit in the holder. I will put the bit into the holder very loosely. Then put the holder and bit in to the “alignment port”. A very light pressure on the back end of the bit will push it forward until it hits the metal stop in the “alignment port”. I then look in the top of the “port” and watch as the metal spring fingers ‘grab’ the flutes of bit and rotate it into the correct position. If you are wondering what I am talking about then give the bit a little twist and watch as the spring fingers “grab” the flutes and rotate the bit back into position. I then tighten up the holder a little at a time making sure the fingers keep the bit in the correct axial position relative to the holder.

It sounds complicated but by looking in the top of the alignment port is becomes “intuitively obvious” what the fingers are trying to do. The metal stop is precisely setting the depth of the bit in the holder and the fingers are precisely defining the axial rotation of the bit with regards to the holder. So just do the best you can to help them “do their thing”, slowly tighten the holder to secure the bit, and in 30 seconds you are ready to go.

The “split point bit” operation – well I have not figured that out yet but I do know you can completely grind the end of a bit off if you are not careful.
 
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Highpower

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+1 on holding finger pressure (pushing the bit into the stop) on the drill shank as you tighten the chuck. When you pull the chuck out and are ready to grind, look at the chuck jaws from the rear and make sure they are not "leaning". If you over-tighten the chuck they will do that, and twist the bit out of position. Just loosen the chuck slowly until the jaws are all pointing straight into the center.
 

firbikrhd1

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I have an older model Classic Drill Doctor 750 and have found that many times it doesn't make the correct clearance angle when using the lips to position the bit. This tool ahs not been abused and only lightly used so I'm certain it isn't damaged. Whether this is a defect in the sharpener or or if it has something to do with the helix angle of the bits being sharpened, I can't say. I suspect that the helix angle of the bit would affect the position of the tip and hence the relief angle since the lips grip the helix to obtain the supposed proper position. For me, a work around for has been to use the lips to position the bit, do a trial sharpening and if the clearance isn't correct rotate the bit slightly in the holder and resharpen. Usually, with my bits I need to rotate clockwise but, again, depending on the helix, counter clockwise may also be necessary.

Perhaps the updated models have addressed this issue. I would want to know more before I purchased another as I am not completely satisfied with mine.
 

irishwoodsman

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all my drill bits i do by hand and eye and gage[the way the military course taught us] it never fails]:biggrin:
 

HMF

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Thank you everyone, for the advice.
I have printed out your replies for reference.

The DD X750 arrived yesterday evening.
I am going to watch the CD and see if I "get it".

I am also going to start on getting my 1960 vintage Baldor 500 working, but that will take time.

Meantime, I won those 500 drills on Ebay, and some need sharpening, and I can practice on them.


Walter- the Baldor 500 is 3 phase. I have an older Teco VFD someone gave me and will need to clean up the motor,
check the bearings, and figure out how to wire the VFD to it using the old control box (on-off-reverse).
I'm going to start another thread on doing that.


Nelson
 

jgedde

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Nelson,

Aa the owner of the DD 750X, I can state that it CAN give good grinds, and CAN split points properly. However, both take some finesse and practice.

My first advice to you would be to avoid split points until you get the hang of sharpening standard 118 degree point bits. When you master this, and understand the geometry, I can discuss how to get split points to work right in a way that will make sense in text. It doesn't work well the way the say to do it and usually results in a bit that's cut away way too much. Also, my DD needed to have the axial position of the wheel on the shaft tweaked slightly to get good splits.

In any case, you'll probably have to finnagle the lock nut and the retaining spring on the diamond wheel to get vibration down.

Also, the manual isn't entirely clear on setting the point angle vs the relief angle. The usey the same numbers (i.e. 118 or 135) for both whereas my understanding of drill geometry measures the included angle between the points as the point angle and the relief angle as the angle generated between the cutting edge and the trailing edge of the lips (typically 5 to 20 degrees, usually around 12). The lock screw and pivot adjustment controls the point angle, the chuck setup guide (the part with MTO adjustment) controls the relief angle.

You'll know you have the hang of sharpening (not split pointing) when you chuck up your newly sharpened bit in your drill press, drill a hole into aluminum, and it cuts like butter with a smooth sided hole. The final check is to measure hole diameter vs drill diameter. When they agree within 0.002 or so, you've mastered it! If the drill cuts oversize, your grind is not symmetrical with respect to the chisel point.

Also, the optional 100 grit coarse wheel is a valuable option for large bits and when splitting points on larger bits.

John
 

kd4gij

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I have had my 750 clasic for over 15 years now have sharpend thousends of drills with it. Simple easy to use.
 

Mike Gibson

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I have a DD750 and it performed well for a few years and then it started to produce similar grinds as you describe. I opened it up and inspected for anything obvious. I did not find anything. I set it aside for the last couple of years but recently I got it back out and tried again. This time when I did the lip alignment I made sure the chuck did not turn to the right as I tightened the chuck. Worked great. I checked again and found there was a slight movement to the right. Now I know not to tighten without holding each end of the chuck.

I have an older model Classic Drill Doctor 750 and have found that many times it doesn't make the correct clearance angle when using the lips to position the bit. This tool ahs not been abused and only lightly used so I'm certain it isn't damaged. Whether this is a defect in the sharpener or or if it has something to do with the helix angle of the bits being sharpened, I can't say. I suspect that the helix angle of the bit would affect the position of the tip and hence the relief angle since the lips grip the helix to obtain the supposed proper position. For me, a work around for has been to use the lips to position the bit, do a trial sharpening and if the clearance isn't correct rotate the bit slightly in the holder and resharpen. Usually, with my bits I need to rotate clockwise but, again, depending on the helix, counter clockwise may also be necessary.

Perhaps the updated models have addressed this issue. I would want to know more before I purchased another as I am not completely satisfied with mine.
 

HMF

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A user named "EddyCurr" made a test of the DD on some bits over at HSM:

http://bbs.homeshopmachinist.net/showthread.php?t=51863&page=5


A neighbor's no-name 3/8" drill
2012.01.11_DrillDoc_01.jpg
Before beginning.
2012.01.11_DrillDoc_02.jpg
After a first pass. A check with a drill gage showed an angle of 122º
and a visual of the heel suggested the relief angle was shallow. The
width of the chisel edge measures 5/64" (1.98 mm).

The wheel is the OEM 180 grit. It leaves a coarse finish but it does not
have much use at this point. Perhaps after some wear knocks down the
high spots, the wheel will leave a smoother finish.

Some steps/facets are apparent. The expected result on the end face
running from the cutting edge to the heel is supposed to be one
smooth continuous surface. The trouble-shooting section in the
manual suggests the steps may be due to hesitant wrist action - I
thought I worked the chuck smoothly.
2012.01.11_DrillDoc_03.jpg
After a second pass.

Before continuing, I reduced the drill point angle setting so that the indicator
arrow was aimed at the base of the '118º' numerals instead of at the middle
of them. This change reduced the finished angle from the 122º shown above
to the desired 118º.

Also, during the step for positioning the drill in the chuck, I inserted the
chuck one notch CCW (to the direction of '+' on the sharpener) from the
straight up (12 o'clock) position. This increased the relief angle.

After resharpening to reflect these changes, a Split Points operation was
performed. As shown, I believe that the points are Under Split - too little
material has been removed to be considered an optimal result. The chisel
edge shown measures 1/32 (0.79 mm). Oh well, it is narrower than as
supplied new. Both cutting edges are equal in length.

The steps/facets are present again. If anything, they are more prominent.
I was consciously trying to be smooth. (I am thinking about applying
some kind of lubricant to the surfaces between the chuck and the
receptacle it rotates in for the next trial.)

The face shown in the right-most image appears dark as if over-heated.
This is just a result of lighting, it is bright to the eye.


More of the neighbor's drills
2012.01.13_DrillDoc_04.jpg
A 5/16" before beginning.
2012.01.13_DrillDoc_05.jpg
Notice that the finish is somewhat less coarse - perhaps due to some wear,
but also likely a result of reduced feed pressure.

Also notice that the steps/facets are gone. The machine had been operated
on top of a piece of corrogated cardboard on the bench - I saw that there
was some movement during sharpening and found that the faceting went
away when the machine was held firmly on a solid surface.
2012.01.13_DrillDoc_06.jpg
This is a 1/4". No 'Before' image, but the 'After' shows improved results, too.

Back on the surface finish.
.

2012.01.11_DrillDoc_01.jpg

2012.01.11_DrillDoc_01.jpg

2012.01.11_DrillDoc_02.jpg

2012.01.11_DrillDoc_02.jpg

2012.01.11_DrillDoc_03.jpg

2012.01.11_DrillDoc_03.jpg

2012.01.13_DrillDoc_04.jpg

2012.01.13_DrillDoc_04.jpg

2012.01.13_DrillDoc_05.jpg

2012.01.13_DrillDoc_05.jpg

2012.01.13_DrillDoc_06.jpg

2012.01.13_DrillDoc_06.jpg
 

pdentrem

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It is important to be consistent on you part. I am still working on technic on mine.
 

markbxr400

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Not a "how to", but a "what to" - most of my broken bits are small ones that I snap trying to go through relatively thin material. While I used to throw these away, now I resharpen. The stubby bits are much stronger than the long ones and have plenty of length left to make it through.

Mark
 

randyjaco

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Nelson,
Change your wheels carefully. The height of the wheel is critical. The mandrel that holds the wheel is mounted to the shaft by friction and can move up and down on the shaft. If the wheel is to high or too low, it will give you fits in getting the bits to sharpen properly. I made a wheel height gauge and now use a wrench to twist off the wheels rather than pull them off or push them on.

Randy
 

burnrider

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+1 on the drill doctor

I had one for a long time. Never figured it out, then one day took the time to play with it.

-Learn to put the flute vertical (narrow part) with the plastic splines at 12 and 6 o'clock before it goes into the gauge. Leave about 1/2" to start on a snug chuck for adjustment.

-For bigger bits, Make 1 turn. If the stone is cutting it at the top, step to your grinder with a protractor and take it closer to the 118 degree mark. Easier on the diamond wheel.

-After a few circles, re-gauge for length in the gauge and set the drill as needed.

-Clean with compressed air & follow up with spray silicone. Makes the plastic chuck smooth, and easy to operate.

-The stock wheel was #100 grit, seems to work well.

-Spent a lot of years free hand grinding the angles. It pays off when using the DD. I was close on a lot of drills, not as close as the DD.
 

brasssmanget

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Very interesting thread. I've been debating getting a DD, since a lot of my drills are getting dull. I attempts at hand sharpening are hit and miss it seems, so I've been looking for affordable machines to make it easier. I have read elsewhere that these DDs are very hard to learn to use and get good results, so this information is very enlightening and encouraging.
 

burnrider

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Very interesting thread. I've been debating getting a DD, since a lot of my drills are getting dull. I attempts at hand sharpening are hit and miss it seems, so I've been looking for affordable machines to make it easier. I have read elsewhere that these DDs are very hard to learn to use and get good results, so this information is very enlightening and encouraging.
3 of us (friends) who initially bought DD had the same experience. They tried it with no success, were intimidated, and set it aside. We have different levels of shop skill. If they saw it done one time, they could use it with confidence. I haven't cut the split angles to this point.
 

Giles

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+1 on holding finger pressure (pushing the bit into the stop) on the drill shank as you tighten the chuck. When you pull the chuck out and are ready to grind, look at the chuck jaws from the rear and make sure they are not "leaning". If you over-tighten the chuck they will do that, and twist the bit out of position. Just loosen the chuck slowly until the jaws are all pointing straight into the center.
That is exactly the reason I exchanged the first the one I bought. The more expensive replacement model was no better.
I considered it an inferior design and returned it.
That was a few years ago and I would have thought they corrected it by now.
I found it much cheaper to replace bits smaller then 3/16" I can see how to sharpen the larger ones.
Some people love them but it was just a big disappointment for me.
 
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